The name “wolf spider” encompasses a large family of spiders, most of which are large, dark-colored and athletic. Unlike most spiders that catch their prey in webs, wolf spiders violently hunt it down using their strong bodies and sharp eyesight. These spiders also exhibit unique parenting habits that are of great interest to scientists.

Wolf spiders live almost everywhere in the world, according to the BioKids. They are especially common in grasslands and meadows, but also live in mountains, deserts, rainforests and wetlands — anywhere they can find insects to eat.

Appearance

Wolf spiders are usually brown, grey, black or tan, with dark markings — most commonly stripes, according to the Missouri Department of Conservation. Their coloring is effective camouflage, helping them catch their prey and keep safe from predators. They range from a quarter of an inch to over an inch (6.4 millimeters to 3 centimeters) long, with males typically smaller than females.

Jo-Anne Nina Sewlal, an arachnologist at the University of the West Indies in Trinidad, told Live Science that wolf spiders have a “distinctive eye arrangement, where the front or anterior row is composed of four small eyes of roughly the same size arranged in almost a straight row. The back or posterior row is arranged in a V-pattern with the apex next to the anterior row.” Wolf spiders have excellent night vision, and primarily hunt in the dark. “They are also quite easily detected at night due to their eyeshine,” she said.

Bite

According to the Pennsylvania State University Entomology Department, wolf spiders will bite when threatened but their venom is not very harmful to humans. Human victims may exhibit some redness or swelling but no serious medical problems have ever been reported.

Habits and feeding

Wolf spiders are solitary creatures that roam alone in the night, stalking prey. According to Sewlal, they are “mostly nocturnal and often mistaken for tarantulas.” According to the Missouri Department of Conservation, they typically live on the ground, though some are known to climb partly up trees to catch their prey. Some species hide in vegetation or leaf litter, while others dig tunnels or use other animals’ tunnels. Some wolf spiders hunt in a set territory and return to a specific place to feed, while others wander nomadically with no territory or home.

Wolf spiders eat mostly ground-dwelling insects and other spiders. Especially large females may eat small vertebrates, according to BioKids. Some species chase down and grab their prey, while others wait for it to walk by and ambush it. Wolf spiders often jump on their prey, hold it between their legs and roll over on their backs, trapping their prey with their limbs before biting it.

Wolf spiders use their keen eyesight, camouflage coloring, speedy movements and high sensitivity to vibrations to be aware of and keep safe from predators. They will bite when threatened. According to the University of Michigan Department of Conservation, however, wolf spiders are also an important food sources for lizards, birds, and some rodents.

Mating

According to BioKids, wolf spiders, who use their eyes more than many other types of spiders, use visual cues in mating. The males signal their interest to females by waving their pedipalps (short, sensory appendages near their mouths) in special patterns or banging them together.

After mating, female wolf spiders lay several dozen or more eggs and wrap them in silk, creating an egg sac. “Female wolf spiders carry their egg sacs attached to her spinnerets,” said Sewlal. If the female is separated from the egg sac, she will search furiously for it. Mothers are known to exhibit aggressive behavior when carrying their egg sacs.

This maternal behavior doesn’t stop after the eggs hatch. “After hatching, the spiderlings climb on their mother’s back and she carries then around for several days,” said Sewlal.

Male wolf spiders typically live for one year or less, while females can live for several years.

Taxonomy/classification

They belong to the Lycosidae family, which is from a Greek word meaning “wolf.” According to the Integrated Taxonomic Information System (ITIS), the taxonomy of wolf spiders is:

Kingdom: Animalia

Subkingdom: Bilateria

Infrakingdom: Protostomia

Superphylum: Ecdysozoa

Phylum: Arthropoda

Subphylum: Chelicerata

Class: Arachnida

Order: Araneae

Family: Lycosidae

Genera & species: There are more than 100 genera and about 2,300 species of wolf spiders; 200 species live in the United States. The Carolina wolf spider (Hogna carolinensis) is the official state spider of South Carolina, which is the only state that has a state spider.

Editor’s Note: If you’d like more information on this topic, we recommend the following book:

Jessie Szalay is a contributing writer for Live Science. She covers animals, health and other general science topics. Her work has appeared in the Jewish Daily Forward, National Geographic Traveler — Intelligent Travel, Killing the Buddha, Waccamaw Journal and elsewhere. Jessie is finishing her master's degree in nonfiction writing at George Mason University and holds a bachelor of arts degree from Kenyon College. She lives in Washington, D.C., and is working on a book about the sociological and psychological practice of othering.